{"id":939791,"date":"2026-07-16T22:38:17","date_gmt":"2026-07-16T22:38:17","guid":{"rendered":"https:\/\/www.europesays.com\/us\/939791\/"},"modified":"2026-07-16T22:38:17","modified_gmt":"2026-07-16T22:38:17","slug":"tiny-us-crystal-sensor-measures-extreme-magnetic-fields-for-fusion","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/us\/939791\/","title":{"rendered":"Tiny US crystal sensor measures extreme magnetic fields for fusion"},"content":{"rendered":"

A team of US researchers has developed a tiny laser-based crystal sensor that can track intense magnetic fields in some of the harshest environments, and improve diagnostics for future fusion power plants. <\/p>\n

For the sensor, the team at Sandia National Laboratories used a rare-earth garnet crystal about the size of a pencil eraser. The device can operate in conditions that often overwhelm conventional magnetic field sensors. <\/p>\n

These include intense radiation, electromagnetic interference, and fusion plasma. The sensor has been submitted for the 2026 R&D 100 Awards, which is an annual competition recognizing the world\u2019s 100 most innovative technologies.<\/p>\n

Israel Owens, PhD, a Sandia physicist and co-inventor of the sensor, pointed out that the team is satisfied with the progress. \u201cWe think this technology is a pretty major improvement in measuring magnetic fields,\u201d he stressed. \u201cWe think it\u2019ll be essential especially for research in fusion, high-energy physics and the power utilities industry.\u201d<\/p>\n

Inside the sensor<\/p>\n

The device uses a small laser, a rare-earth garnet crystal, two optical filters, and a light detector. As the laser passes through the crystal, its polarization rotates. In addition, exposure to a magnetic field<\/a> changes the amount of that rotation, and allows the sensor to precisely measure the field\u2019s strength.<\/p>\n

According to Sandia, the crystals are made from rare-earth materials<\/a> like terbium scandium aluminum garnet (TSAG) and terbium gallium garnet (TGG). They are well suited for measuring magnetic fields because their optical properties change in response to electromagnetic forces.<\/p>\n

\"\"Sandia physicist Israel Owens, PhD, adjusting the optics of his laboratory system.
Credit: Craig Fritz<\/a><\/p>\n

The researchers started developing the sensor in 2021. Their goal was to improve the measurements inside their Z Machine, the world\u2019s most powerful lab radiation source. It is utilized for\u00a0basic science research, studies of\u00a0magnetized liner inertial fusion, and for national security applications<\/p>\n

The team tested the sensor at Sandia\u2019s High-Energy Radiation Megavolt Electron Source III (HERMES III<\/a>) and the Short Pulse High Intensity Nanosecond X-Radiator (SPHINX). The device matched the performance of conventional magnetic sensors while providing more consistent measurements in harsh environments.<\/p>\n

Owens said the sensor is more accurate and operates where conventional sensors fail. \u201cWe\u2019ve done quite a bit of testing over at SPHINX, and we saw less statistical spread compared to conventional sensors,\u201d he added. <\/p>\n

As per the team, the garnet-based sensor would not require frequent calibration and maintenance like conventional sensors. This could reduce operational costs. Since it\u2019s electrically insulating rather than metallic, it also avoids problems that can affect electronic probes in radiation-heavy environments.<\/p>\n

The technology could be particularly valuable for fusion energy research, where powerful magnetic fields are utilized to confine superheated plasma. Accurately monitoring those magnetic fields is essential for understanding plasma behavior and maintaining stable reactor operation.<\/p>\n

Owens said that the sensor may eventually function inside plasma environments where conventional metallic sensors short out, and fiber-optic sensors degrade due to radiation exposure. \u201cOur technology has the unique capability of working in areas where conventional sensors would short out,\u201d he noted in a statement<\/a>.<\/p>\n<\/p>\n

However, the technology remains under development. After successful testing in air and vacuum, the Sandia team has begun evaluating the sensor in low-density plasma. The team ultimately plans to test it in the high-density plasma conditions required for commercial fusion systems.<\/p>\n

Bryan Oliver, director at Sandia\u2019s Radiation and Electrical Sciences center stressed the importance of the sensor. \u201cThe magneto-optical sensor technology is a game-changing diagnostic for measuring varying magnetic fields in difficult radiation and electromagnetic environments,\u201d he concluded. The team secured a patent<\/a> in December, and one company has licensed the technology.<\/p>\n","protected":false},"excerpt":{"rendered":"A team of US researchers has developed a tiny laser-based crystal sensor that can track intense magnetic fields…\n","protected":false},"author":3,"featured_media":939792,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_share_on_mastodon":"0"},"categories":[25],"tags":[6574,76938,3555,45786,18434,492,3051,172831,72622,159,24614,67,132,68],"class_list":["post-939791","post","type-post","status-publish","format-standard","has-post-thumbnail","category-physics","tag-energy-amp-environment","tag-fusion-energy","tag-inventions-and-machines","tag-laser","tag-magnetic-fields","tag-physics","tag-plasma-physics","tag-rare-earth-elements","tag-sandia-national-laboratories","tag-science","tag-sensor","tag-united-states","tag-unitedstates","tag-us"],"share_on_mastodon":{"url":"","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/939791","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/comments?post=939791"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/939791\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media\/939792"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media?parent=939791"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/categories?post=939791"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/tags?post=939791"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}